Magnetic drill chuck assembly



March 25, 1958 APPLEBY 2,828,131

MAGNETIC DRILL CHUCK ASSEMBLY Filed Dec. 11-. 1955 l6 I Z /8 5. I I9 s I N, Z3 H m f" INVENTOR. Dav/a -K.A,0p/eby United States 'Thisfinvention, relates'itolmagneticj connecting and selfcentering, means; for objects which are. oftherwis'ejunconnected, with each; other, and, are,'o'therwise not. confined tolaicenter'ed relationlto each other. and which are to be crotatedfiihdr iv-ing ,andldriven relationto each other.

Thesp r iiliary object oflthelinventionlislto provide practica1, a.ud: efi'ic ient 1 means'o'f this a character which; enable qpick,,-,accura;te, .andeasy centeringlofgsuh askmicro drills withoutfresort ,tqpfeseiitly employed, various devices :and expedients whose ,emplqyment consumes time and. effort, andll involve's substantial, expense for, their. provision and maintenance;

Another, important ,ohject of v, the invention isjtov providehmeans of the-character. indicatedlaboveiwhich. are composed-of; altm'inimum number ofhsimpleparts, and whihcanfbelmadeinl rugged, ,servieeable, and attractive 'formslatrelat'ivly low, cost.

Other'impor'tant objects "and'adva ntageous features-or" the invention .will be apparent -.fromthe, following description ar'fd'th'e "accompanying drawings, wherein; for purposes of illnstratinfionly; specificien ibfodiments of the inventioniare set forth in detail.

- Figure; li fis' a substantially "central; vertical Jtrans'verse "BGllOIl through one embodiment;

fflFigu'reil is a' hor'izohtal s'ection on the line [Figure j3f-is 'a substari chuck member for 'u'sewit'h the'einbodiment of Figure 1;

Figure 4 is anl'enlarged: sidehelevation of another embedimentaof the invention, a drill. centering operation being shown as performed withiallead pencil-t;

FigureS "is "a to 'pran view, on a reduced scale, of the magnetizable chuck member of Figure 4; and

Figure 6 is a bottom plan view, on a reduced scale, of the magnet-bearing member of Figure 4.

Referring in detail to the drawings, wherein like numerals designate like parts throughout the several views, and first to Figures 1 and 2 thereof, the embodiment of the invention therein shown is generally designated 7.

The assembly 7 comprises a magnet-bearing member 8, here shown as a solid cylindrical body of aluminum or other suitable non-magnetizable material, having a frustro-conical upper portion 9 having an axial socket 10 in which is plug-fitted a shank 11 which is arranged for engagement in the chuck of a drill press or the like (not shown).

The underside 12 of the member 8 is flat and squared with the axis of the member 8, and is provided with a relatively large diameter circular and concentric recess 13, in which is secured, in suitable manner, a circular permanent magnet 14 having a plain underside 14' which is spaced upwardly at a slight distance above the underside of the member 8.

The assembly 7 further comprises the magnetizable chuck member 15 which is here shown as a circular cup having a plain bottom wall 16 and a peripheral rim or side wall 17 rising from the bottom wall 16. The cup I l tially central,transverse.verticaL -seetion .tak'en' through another "form-of magnetizable 2 l slisymade offaluminu'm or other suitable'non magnetizable material, secured in the cup lsand' covering the bottom wall'1'6 is a relatively thin magnetiiableiplateim. The-internal diameterofthe rim 17 is slightlylarge'r than 6 theoutsideidia'rneterlo'fthe cylindrical part of 'the'magnetbearingmemberf8=.v -Tl'legc'up 15, can also be ma'de'entire- 1y of "steel if desired;

, Plreferably formed integral'with the. cupbotto'm wall'1'6 is an axialdep'ending boss 19" which terminates 'in a chuck 10, headp20 provided with an axial socket 21,t-arranged"to receive "the upper 'endio'f'a. micro drill"bit"2"2', the latter beingsecurablejinithasocket.21" by a set screw 23'traversing;the.,chuc'k head 20.

Anotherl irorm off magnetizable chuck inemb'er desig- .structionamthemenaiheijv I'Sioff Figures 1' and 2; is" usable with; tIieJma'gn'e't-bear'ingQmember, '81 thereof, but has. a differentfforr'no "hiick"head, which involves a slot 24 in .thel'lowe r,endQofj'thelboss 19", thejprovision-of external 20, screw threads'i2ionfltheolower-end of the boss 19,,a

healeljfilonlthe,;lower;entlfofith'e boss 19, and, anut 27 threaded ionthefthreadsI251 Thelb'ore o'f fthejnut 27is tc'h okedlat mwer, end to provideacam b'vel'ZS' for compressiveengagementwith the bevel '26 'to clamp a drill bit inlhe, boreof'thejboss 19'.

In. operation, 'the. magnet-bearingmember 8 being e'ngagedf'in, a. drilli press chuck ..(not. shown) andth'e magnetizable chuckjm'ember 15 being, engaged ;over1 the lower end, or the -magnet bearing "body, '8, with the magnetpl l 30.,holdi-ngtthe member/15in place. against the. underside 1,4 of thebody 8 ,;and, therassembly being rotatedfby the drill ,pre s,.,'fingers Ofia hand are engaged fwithl the, rim '17 andrl-the member '15Qis 'shifted;relatiizej'toitlie; member-f8 to ,a, sliglj1'tly. eccentric; or ofi-l'center vpo's' 011,, this mevement heingproviddjfor byft'he. .-largerl insidediametenof the rim 17..

Theupoint' 29 of f afpencil 30,-,0'1' some. other, suitable implement, 'isitheniapplied againstt-thefsideiofiheirotating aim -biti2 2, as: illustrated inFigureA and jmaliipulated so 40. asi'tol .ce'nterthe drill bit '22..

The embodiment .of .ith'e inventionfshown' .in Figures, 4 throughf6 ofthe drawings, and generally dsigna'ted'7a, differs ,fromithose shown lin Figures L1, to. 3, ,only, in-lthe ovisiemor. equally, circumferentially, spaced. and," dia- 45,. metrically,opposednotches .31. in the underside/12h, of the magnet-bearing.body..8a, (and irrtheipr'ovisionto'f similarly arrangedlugs 32 on the upper'edge 33"o'fthe magnetizable chuck member wall 16a. The lugs 32 are slightly narrower than the notches 31, and the lugs 32 are engaged in the notches 31 in the assembled condition of the device 7a, with the lower side 12a of the body 8a resting upon the upper edge 33 of the wall 16a of the member 15a.

The operation of the device of Figures 4 through 6 is the same as with the device 7 of Figures 1 through 3.

The arrangements described hereinabove permit of quicklyand easily manually separating the magnetizable chuck members from the magnet-bearing members, while the devices are being rotated, for replacement of drill bits, and other magnetizable chuck members may be substituted for those so removed, whenever desired, and without stopping the associated drill press, or other manipulations or delays.

It is to be noted that the device can be operated in either vertical or horizontal positions with equal elficiency.

What is claimed is:

1. An alignable holder for a drill and the like comprising a shank member, a drill retaining member, magnetic coupling means providing a constant attractive 7 force incorporated in said shank member and said retaining member for operatively engaging said members,

said members having planar contacting surfaces to per mit lateral movement of said members relative to each other, and said constanfattractive'forcebeing of sufficient strength to prevent relative angular movement of said tained drill.

the internal diameter of said rim being greater than the "outside diameter of said magnet-bearing member'bo'dy,

2.' An alignable holderas set forth in claim 1 wherein lindrical member and said drill retaining member is comprised of a cup-shaped member whose inside diameter is u said shank member is comprised of a substantially cy- 3. An alignable holder as set forth in claim .2 wherein of nonmagnetic material and a plate of magnetic material forms the bottom wall of said cup.

4 In a magnet drill chuck assembly comprising a magnet-bearing member anda magnetizable chuck member,

said magnet-bearing member comprising a cylindrical body having an upper end and a lower end, a shank on the upper end of said body engageable in the chuck of a drill press, the lower end of said body being provided with a circular recess, a circular magnet secured in said recess, said magnet having an underside, said magnetizable member comprising circular cup having a bottom wall and a peripheral rim rising from said bottom plate, the internal diameter of said rim being greater than the outside diameter of said magnet-bearing member body, a magnetizable plate secured upon said bottom plate, and axial drill chuck means fixed to and depending from said bottom plate, the magnetizable plate being frictionally and slidably engaged with the underside of said body and held so engaged by the attraction of said magnet with said rim freely surrounding said body, said magnetizable Q chuck member being manually shiftable radially relative,

to the magnet-bearing body to center a drill bit in said chuck means relative to the magnet-bearing body.

the upper end of said body engageable in the chuck of 45" a drill press, the lower end of said body being provided with a circular recess, a circular magnet'secured in'said recess, said magnet having an underside, said magnetizv able member comprising a circular cup having a bottom 'wall and a peripheral rim rising from said bottom plate, 50 697,868

a magnetizable plate secured upon said bottom plate, and axial drill chuck means fixed to and depending from said bottom plate, the magnetizable plate being frictionally and slidably engaged with the underside of said body and held so engaged by the attraction of-said magnet with said rim freely surrounding said body, said magnetizable chuck member being manually shiftable radially relative to the magnet-bearing body to center a drill bit in said chuck means relative to the magnet-bearing body, the magnet having an underside, spaced upwardly from the underside of said body.

6. In a magnet drill chuck assembly comprising a magnet-bearing member and a magnetizable chuck member, said magnet-bearing member comprising a cylindrical body having an upper end and a lower end, a shank on ,the upper end of said body engageable in the chuck of a drill press, the lower end of said body being provided with a circular recess, a circular magnet secured in said recess, said magnet having an underside, said magnetizable member comprising a circular cup having a bottom wall and a peripheral rimrising from said bottom plate, the internal diameter of said rim being greater'than the outside diameter of said magnet-bearing member body, a magnetizable plate secured upon said bottom plate, and axial drill chuck means fixed to and depending from said bottom plate, the magnetizable plate being frictionally and slidably engaged with the underside of said body and held so engaged by the attraction of said magnet with said rim freely surrounding said body, said magnetizable chuck member being manually shiftable radially relative to the magnet-bearing body to center a drill bit in said chuck means relative to the magnet-bearing body, the underside of said body being plain and continuous.

References Cited in the file of this patent UNITED STATES PATENTS- 1,369,491 Straehle Feb. 22, 1921 1,398,679 Clark Nov. 29, 1921 A 1,523,770. Hanson Jan. 20, 1925 2,147,204 Laird Feb. 14, 1939 2,297,064 McKinley Sept. 29, 1942 2,360,928 Beechlyn Oct. 24, 1944 2,399,808 Jones May 7, '1946 v FOREIGN PATENTS I.

491,920 Germany Mar. 12 1929 Germany Oct. 25,"1940 

